2009 Annual Science Report

Astrobiology Roadmap Objective 5.3 Reports Reporting  |  JUL 2008 – AUG 2009

Project Reports

  • Astrobiology of Icy Worlds

    Icy worlds such as Titan, Europa, Enceladus, and others may harbor the greatest volume of habitable space in the Solar System. For at least five of these worlds, considerable evidence exists to support the conclusion that oceans or seas may lie beneath the icy surfaces. The total liquid water reservoir within these worlds may be some 30 to 40 times the volume of liquid water on Earth. This vast quantity of liquid water raises two questions: Can life emerge and thrive in such cold, lightless oceans beneath many kilometers of ice? And if so, do the icy shells hold clues to life in the subsurface? We will address these questions through four major investigations namely, the habitability, survivability, and detectability of life of icy worlds coupled with “Path to Flight” Technology demonstration. We will also use a wealth of existing age-appropriate educational resources to convey concepts of astrobiology, spectroscopy, and remote sensing; develop standards-based, hands-on activities to extend the application of these resources to the search for life on icy worlds.

    ROADMAP OBJECTIVES: 1.1 2.1 2.2 3.1 3.2 3.3 3.4 4.1 5.1 5.3 6.1 6.2 7.1 7.2
  • AbGradCon 2009

    The Astrobiology Graduate Student Conference (AbGradCon) was held on the UW campus July 17 – 20 2009. AbGradCon supports NAI’s mission to carry out, support and catalyze collaborative, interdisciplinary research, train the next generation of astrobiology researchers, provide scientific and technical leadership on astrobiology investigations for current and future space missions, and explore new approaches using modern information technology to conduct interdisciplinary and collaborative research amongst widely-distributed investigators. This was done through a diverse range of activities, ranging from formal talks and poster sessions to free time for collaboration-enabling discussions, social activities, web 2.0 conference extensions, public outreach and grant writing simulations.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 3.2 3.3 3.4 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • AIRFrame Technical Infrastructure and Visualization Software Evaluation

    To create visualizations of interdisciplinary relationships in the field of astrobiology, this component of the AIRFrame project involves creating a data model for source documents, a database structure, and evaluating off-the-shelf visualization software for possible application to the final project.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 3.2 3.3 3.4 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • Biosignatures in Ancient Rocks

    The Earth’s Archean and Proterozoic eons offer the best opportunity for investigating a microbial world, such as might be found elsewhere in the cosmos. The ancient record on Earth provides an opportunity to see what geochemical signatures are produced by microbial life and how these signatures are preserved for geological time. Researchers have recognized a variety of mineralogical and geochemical characteristics in ancient rocks (sedimentary and igneous rocks; paleosols) that may be used as indicators of: (i) specific types of organisms that lived in the oceans, lakes and on land; and (ii) their environmental conditions (e.g., climate; atmospheric and oceanic chemistry). Our project addresses the following questions: Are some or all of these characteristics true or false signatures of organisms and/or indicators of specific environmental conditions? Do a “biosignature” in a specific geologic formation represent a local or global phenomenon? How are the biosignatures on Mars and other planets expected to be similar to (or different from) those in ancient terrestrial rocks?

    ROADMAP OBJECTIVES: 1.1 3.2 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • Advancing Methods for the Analyses of Organics Molecules in Microbial Ecosystems

    Eigenbrode’s GCA work over the past year has largely focused on advancing protocols for the extraction and analysis of complex organics molecules in iron-oxide rich samples regarded as analogs to groundwater seeps and ancient surface water environments on Mars and ancient Earth. Eigenbrode has succeeded with some advance in methods for organic extraction and analysis for samples that include iron seep sediments, cultured iron bacteria, and terrace sediments of the Rio Tinto. In addition, Eigenbrode has been part of a successful study aimed at understanding microbial metabolisms and ecological evolution of Neoarchean using Fe, S, and C isotopic records.

    ROADMAP OBJECTIVES: 2.1 4.1 5.1 5.2 5.3 6.1 7.1
  • Amino Acid Alphabet Evolution

    All life on earth uses a standard “alphabet” of just 20 amino acids. Members of this alphabet links together into different sequences to form proteins that then interact to produce living metabolism (rather like the English of 26 letters can be linked into words that interact in sentences and paragraphs to produce meaningful writing). However, a wealth of scientific research from diverse disciplines points to the idea that many other amino acids are made by non-biological processes throughout the universe: put simply, we have no idea why life has “chosen” the members of its standard alphabet. Our project seeks to gather and organize the disparate information that describes these non-biological amino acids, to understand their properties and potential for making proteins and thus to understand better whether the biology that we know is a clever, predictable solution to making biology – or just one of countless possible solutions that may exist elsewhere.

    ROADMAP OBJECTIVES: 1.1 3.1 3.2 3.4 4.1 4.3 5.1 5.3 6.2 7.1 7.2
  • Extremophile Ribosomes

    We will compare biochemistry and the three-dimensional structures of ribosomes from modern organisms on particular lineages of the tree of life. Extremophiles are of special interest due to their ability to thrive in environments that reminiscent of early biotic earth.

    ROADMAP OBJECTIVES: 5.3
  • Biosignatures in Relevant Microbial Ecosystems

    In this project, PSARC team members explore the isotope ratios, gene sequences, minerals, organic biomarkers, and other biosignatures in modern ecosystems that function as analogs for early earth ecosystems, or for life that may be present elsewhere in the solar system and beyond. Many of these environments are “extreme” by human standards and/or have conditions that are at the limit for microbial life on Earth.

    ROADMAP OBJECTIVES: 4.1 4.3 5.1 5.2 5.3 6.1 7.1 7.2
  • Relationship Between Hydrogeology and Microbiology at Active Springs

    Springs formed by groundwater discharge may be the most likely sites for supporting life in the past or at present on Mars. We have been studying the processes that govern spatial and temporal variability of water properties at springs and the biological diversity in microbial communities supported by the springs.

    ROADMAP OBJECTIVES: 3.2 5.3 6.1
  • High Level Theory – the Role of Mg2+ in Ribosome Assembly

    We have embarked on a computational evaluation of the role of Mg2+ microclusters observed to form a scaffold for the extant and ancestral peptidyl transferase center. The interaction energies of ribosomal RNA with single and multiple Mg2+ cations are computed, and deconvolved. The results will be compared to those with other metals, to determine why Mg2+ plays a special role in RNA folding.

    ROADMAP OBJECTIVES: 3.2 5.3
  • Evolution of Nitrogen Fixation, Photosynthesis, Hydrogen Metabolism, and Methanogenesis

    We have developed a new line of investigation to complement our work on the biochemistry of complex iron-sulfur cluster enzyme structure, function and biosynthesis with the aim of probing complex iron-sulfur enzyme evolution. We are studying the phylogenetic trajectory of multiple genes involved in complex iron-sulfur cluster function and biosynthesis to probe the evolutionary origin of aspect of hydrogen metabolism and modes of biological nitrogen fixation.

    ROADMAP OBJECTIVES: 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • Ecosphere to Biosphere Modeling – Final CAN-3 Report

    We have created a working model of a microbial mat called MBGC (for Microbial Biogeochemistry). The model examines the internal cycling of oxygen, carbon, and sulfur through a complex microbial ecosystem that may be similar to those found on early earth.

    ROADMAP OBJECTIVES: 4.1 5.3 6.1
  • Bioastronomy 2007 Meeting Proceedings

    The 9th International Bioastronomy coneference: Molecules, Microbes and Extraterrestrial Life was organized by Commission 51 (Bioastronomy) of the International Astronomical Union, and by the UH NASA Astrobiology team. The meeting was held in San Juan, Puerto Rico from 16-20 July 2007. During the reporting period the Proceedings were finalized and will have a publication date of 2009.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 3.2 3.3 3.4 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • Interplanetary Pioneers – Final CAN-3 Report

    The possibility of life traveling from earth to beyond, and, in general, life traveling from planet to planet, has captured the public’s imagination for a century or more. We are now poised to assess this possibility with experimentation. In this project, we focus on halophiles – organisms that live in high salt environments – as potential earth life to survive space travel. Thus we have explored high UV and high salt environments, and have flown some of these organisms on European space missions. This year we also began to develop the use of high altitude ballooning to mimic travel beyond the surface of the earth.

    ROADMAP OBJECTIVES: 5.3 6.2
  • Developing New Biosignatures

    The development and experimental testing of potential indicators of life is essential for providing a critical scientific basis for the exploration of life in the cosmos. In microbial cultures, potential new biosignatures can be found among isotopic ratios, elemental compositions, and chemical changes to the growth media. Additionally, life can be detected and investigated in natural systems by directing cutting-edge instrumentation towards the investigation of microbial cells, microbial fossils, and microbial geochemical products. Over the next five years, we will combine our geomicrobiological expertise and on-going field-based environmental investigations with a new generation of instruments capable of revealing diagnostic biosignatures. Our efforts will focus on creating innovative approaches for the analyses of cells and other organic material, finding ways in which metal abundances and isotope systems reflect life, and developing creative approaches for using environmental DNA to study present and past life.

    ROADMAP OBJECTIVES: 2.1 2.2 3.1 3.4 4.1 5.2 5.3 7.1 7.2
  • CASS Planning

    The computational astrobiology summer school (CASS) is a two week program, followed by a semester of mentored independent work, which has the following goals:

    - To introduce computer science and engineering (CS&E) graduate students to the field of astrobiology, – To introduce astrobiologists to the tools and techniques that current methods in CS&E can provide, and – To encourage interdisciplinary projects that will result in advances in astrobiology.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 3.2 3.3 3.4 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • RNA Folding and Assembly

    We will characterize the assembly, structure and thermodynamics of the a-PTC by chemical mapping, including hydroxyl radical footprinting1,2 and SHAPE analysis,3 RNase H cleavage, temperature dependent hydrodynamics,4 and computational folding algorithms. In addition we will investigate the effect of freezing aqueous solutions of RNA and DNA molecules on their ability to assemble into larger more complex structures. Freezing nucleic acid solutions concentrates non-water molecules into small liquid pockets in the ice. This enables reactions that can promote the assembly of small segments of nucleic acids into larger complexes.

    ROADMAP OBJECTIVES: 3.2 5.3
  • Chemistry, Origin and Evolution of Subduction Zone Fluids Rising Beneath the Mariana Forearc

    Ultramafic rocks make up the mantle of most rocky bodies in the Solar System. When ultramafic rocks come in contact with liquid water they are altered to serpentinite over a wide range of temperatures, from freezing to about 500ºC. On Earth, plate tectonics provides ample opportunity for this contact to occur, especially in subduction zones. In extraterrestrial environments, serpentinization should occur wherever liquid water comes into contact with mantle-type rocks, such as on Mars and on the parent bodies of asteroids. We have collected waters upwelling through serpentinite mud volcanoes in the forearc region of the Mariana subduction zone in the NW Pacific Ocean. These waters are rich in methane produced inorganically during serpentinization. The methane supports chemosynthetic communites of extremophilic Archaea that thrive at an in-situ pH of 13.1.

    ROADMAP OBJECTIVES: 5.3 7.1
  • Subglacial Methanogenesis and Its Role in Planetary Carbon Cycling

    Methanogens are thought to be among the earliest emerging life forms. Today, the distribution of methanogens is narrowly constrained, due in part to the energetics of the reactions which support this functional class of organism (namely carbon dioxide reduction with hydrogen and acetate fermentation). Methanogens utilize a number of metalloenzymes that have active site clusters comprised of a unique array of metals. The goals of this project are 1) identifying a suite of biomarkers indicative of biological CH4 production 2). quantifying the flux of CH~4~ from sub-ice systems and 3). developing an understanding how life thrives at the thermodynamic limits of life. This project represents a unique extension of the ABRC and bridges the research goals of several nodes, namely the JPL-Icy Worlds team and the ASU-Follow the Elements team.

    ROADMAP OBJECTIVES: 2.1 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • Viral Ecology and Evolution

    This project is aimed at probing the occurrence and evolution of archaeal viruses in the extreme environments in the thermal areas in Yellowstone National Park. Viruses are the most abundant life-like entities on the planet and are likely a major reservoir of genetic diversity for all life on the planet and these studies are aimed at providing insights into the role of viruses in the evolution of early life on Earth.

    ROADMAP OBJECTIVES: 5.1 5.2 5.3 6.1 6.2 7.1 7.2
  • Deep Biosphere Workshop

    This is a Workshop on the use of borehole CORK observatories for microbiological and hydrogeological studies. It is planned to be an international workshop including European and Asian participation. We are also actively targeting early career researchers and those not yet actively involved in deep marine CORK observatory research.

    ROADMAP OBJECTIVES: 4.2 5.2 5.3 6.1 6.2
  • Stellar Effects on Planetary Habitability

    Habitable environments are most likely to exist in close proximity to a star, and hence a detailed and comprehensive understanding of the effect of the star on planetary habitability is crucial in the pursuit of an inhabited world. We model how stars with different masses, temperatures and flare activity affect the habitability of planets. We also address the effect that tides between a star and a planet have on planetary habitability, including the power to turn potentially habitable planets like Earth into extremely volcanically active bodies like Io.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 4.1 4.3 5.3 6.1 7.2
  • Stromatolites in the Desert: Analogs to Other Worlds

    Cuatro Cienegas Basin, a desert oasis in the Chihuahua desert of central Mexico, provides a proxy for an earlier time in Earth’s history when microbes dominated the scenery. The basin hosts active, growing stomatolites, communities of microbes that are covered in carbonates, principally through the action of metabolic processes within the community. Researchers from several NAI teams are actively researching and creating experimental procedures to understand small scale and large scale evolution within these communities, using tools from biology, geology, and astronomy.

    ROADMAP OBJECTIVES: 4.1 4.2 5.2 5.3 6.1 6.2
  • Stoichiometry of Life, Task 1: Laboratory Studies in Biological Stoichiometry

    Living things require a broad menu of chemical elements to function. This project aims to quantify the chemical elements required by prokaryotes – the class of terrestrial organisms thought most similar to those that might be present in extraterrestrial settings – through laboratory experiments. These experiments will also teach us the ways in which such organisms cope with scarcity of the bioessential elements nitrogen, phosphorus and iron. We are also conducting experiments to isolate micro-organisms that use the element arsenic in place of phosphorus, if they exist. In Year 1 we initiated the first stage of these experiments.

    ROADMAP OBJECTIVES: 5.1 5.2 5.3 6.1 6.2 7.1
  • Thermodynamic Efficiency of Electron-Transfer Reactions in the Chlorophyll D-Containing Cyanobacterium, Acharyochloris Marina

    Photosynthesis is the only known process that produces planetary-scale biosignatures – atmospheric oxygen and the color of photosynthetic pigments — and it is expected to be successful on habitable extrasolar planets as well, due to the ubiquity of starlight as an energy source. How might photosynthetic pigments adapt to alternative environments? Could oxygenic photosynthesis occur at much longer wavelengths than the red? This project is approaching these questions by studying a recently discovered cyanobacterium, Acaryochloris marina, which performs oxygenic photosynthesis in environments depleted in visible light but enriched in far-red/near-infrared light. A. marina is the only known organism to have chlorophyll d (Chl d) to use photons in the far-red and near-infrared, whereas all other oxygenic photosynthetic organisms use chlorophyll a (Chl a) to utilize red photons. Whether A. marina is operating more efficiently or less than Chl a-utilizing organisms will indicate what wavelengths are the ultimate limit for oxygenic photosynthesis. We have been conducting lab measurements of energy storage in whole A. marina cells using pulsed, time-resolved photoacoustics (PTRPA, or PA), a laser technique that allows us to control the wavelength, amount, and timing of energy received by a sample of cells.

    ROADMAP OBJECTIVES: 3.2 4.2 5.1 5.3 6.2 7.2
  • Developing New Sampling System, Collection of Juan De Fuca Ridge Basement Fluids

    Our Deep Biosphere project is designed to exploit the unprecedented opportunities provided by the new generation of long-term borehole- observatories installed on the flanks of the Juan de Fuca Ridge (JdFR) by the Integrated Ocean Drilling Program, to study the microbial geochemistry and ecology of the sediment-buried ocean basement. The Drill ship drills deep holes through the sediments into the underlying basaltic rocks and then installs a 'CORK’ observatory consisting of casings, fluid delivery lines with seafloor access-spigots, downhole instruments, and a top plug.

    ROADMAP OBJECTIVES: 3.2 3.3 4.1 5.2 5.3
  • Stoichiometry of Life, Task 2a: Field Studies – Yellowstone National Park

    We are investigating how the element requirements of microbes are affected by element availability in their environment in Yellowstone National Park, where there are extreme variations in the abundances of bioessential elements in addition to extremes of temperature and pH. In Year 1 we organized a multi-disciplinary field expedition to collect samples and conduct experiments. Analyses of these samples is now underway.

    ROADMAP OBJECTIVES: 5.1 5.2 5.3 6.1 6.2 7.2
  • Stoichiometry of Life, Task 2b: Field Studies – Cuatro Cienegas

    Cuatro Cienegas is a unique biological preserve in which there is striking microbial diversity, potentially related to extreme scarcity of phosphorus. We aim to understand this relationship.

    ROADMAP OBJECTIVES: 5.1 5.2 5.3 6.1 6.2
  • Understanding Past Earth Environments

    This project examines the evolution of the Earth over time. This year we examined and expanded the geological record of Earth’s history, and ran models to help interpret those data. Models were also used to simulate what the early Earth would look like if viewed remotely through a telescope similar to NASA’s Terrestrial Planet Finder mission concept. We focused our efforts on the Earth as it existed in prior to and during the rise of atmospheric oxygen 2.4 billion years ago, as this was one of the most dramatic and important events in the evolution of the Earth and its inhabitants.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 4.1 4.2 4.3 5.1 5.2 5.3 6.1
  • Stoichiometry of Life, Task 3b: Ancient Records – Genomic

    The genomic records of modern organisms carry clues to the evolution of the use of elements in biology. We are investigating these records in several ways, with a particular emphasis on the use of metals in enzyme active sites and nitrogen fixation.

    ROADMAP OBJECTIVES: 5.1 5.2 5.3
  • Lau Basin Cruise

    This project revolves around a volcanic eruption at the seafloor at about 1400 m depth. We responded to this eruption using a research ship, the RV Thompson, and the unmanned remotely operated underwater vehicle, JASON. We used the JASON to sample the fluids and rocks associated with the still active eruption to study the microbial ecology and geochemistry of early life at new eruptive sites.

    ROADMAP OBJECTIVES: 5.3 6.1
  • Microbial Ecology in Hawaiian Lava Caves

    We have been studying a microbial biofilm growing at very low light intensities and high temperature and humidity below the entrance of a lava cave in Kilauea Crater, Hawai’i Volcanoes National Park. The cave presents an oligotrophic environment, but condensation of geothermally heated groundwater that vents at the rear of the cave has promoted the development of a complex microbial community, similar in higher order taxonomic structure to copiotrophic soil environments. Given the existence of lava tubes of similar geologic composition on Mars, geothermal activity there may have allowed the existence, or persistence, of complex microbial communities in similar Martian environments, wherein they would be shielded from the effects of harmful UV radiation.

    ROADMAP OBJECTIVES: 5.1 5.3
  • Nordic-UHNAI Astrobiology Summer School – Iceland 2009

    In collaboration with the Nordic Astrobiology Network, we organized an astrobiology summer school held in Iceland from Jun 29-Jul 13, 2009. Participants included 19 graduate students from the US, and 24 students from 16 countries, with a focus on Nordic participants. Activities during the two week program included lectures on the topics of Water, Ice and the Origin of Life in the Universe, a student poster session, field sampling on thermophiles, and labwork and computer modeling activities.

    ROADMAP OBJECTIVES: 2.2 3.1 5.2 5.3
  • Quantification of the Disciplinary Roots of Astrobiology

    The questions of astrobiology span many scientific fields. This project analyzes databases of scientific literature to determine and quantify the diverse disciplinary roots of astrobiology. This is one component of a wider study to build a map of relationships between the constituent fields of astrobiology, so relevant knowledge in diverse fields can be most efficiently inform the study of life in the universe.

    ROADMAP OBJECTIVES: 1.1 1.2 2.1 2.2 3.1 3.2 3.3 3.4 4.1 4.2 4.3 5.1 5.2 5.3 6.1 6.2 7.1 7.2